Tube expander



FIG. 1 is a perspective view of a tube expander showing our new design;

FIG. 2 is an elevational view for both front side and rear side thereof;

FIG. 3 is a left side elevational view thereof;

FIG. 4 is a right side elevational view thereof;

FIG. 5 is a top plan view thereof;

FIG. 6 is a bottom plan view thereof; and,

FIG. 7 is another perspective view thereof. 

CLAIM The ornamental design for a “tube expander,” as shown and described. 